Seasonal dynamics and spatial distribution of herbage diversity on the slopes of Suiyu railway

Seasonal dynamics and spatial distribution of herbage diversity were studied in the vegetation on the slopes of Suiyu railway as compared with the natural slopes.Herbaceous community was investigated in four seasons including March(spring),June(summer),September(autumn) and December(winter) from 2008 to 2009,respectively.The Margalef index,Simpson index,Shannon-Wiener index and Pielou index were analyzed.The results indicated that,the species richness existed prominent difference in the middle slope on the slopes of Suiyu railway(P0.05),the maximum species richness reached 2.376 in autumn.Both species diversity and evenness index had significant difference among different seasons in different location of the slope(P0.05),and the changing of species diversity and evenness index had the same rules with the following order: spring summer winter autumn,while the seasonal changes of species richness,diversity and evenness indices were not obvious on the natural slope.The location of the railway slope affected the species richness prominently(P0.05) rather than diversity and evenness(P0.05),the species richness reached its maximum of 2.164 in summer on the upper slop,2.261,2.376 and 1.983 in spring,autumn and winter on the middle slop respectively.The location of the natural slope only affected the species richness and evenness in autumn significantly(P0.05),moreover,they had different kinds of changing rules.The species richness followed the order as of upper lower middle,whereas,the evenness followed the order as of middle upper lower.There existed larger differences in the aspect of the species richness,diversity and evenness among different vegetation types.The species richness on the natural slope was significantly larger than that on the railway slope,and the vegetation restoration on the natural slope was better than that on the slope of railway.So strengthen the management is key measurement to ecological restoration of railway slope.